Shapley 1

An annular planetary nebula in the constellation
Norma. It was discovered by Harlow Shapley
in 1936. Shapley 1 is unusual among planetaries in that it is neither bipolar
nor a simple sphere of gas. Most ring-like planetary nebulae really consist
of spherical shells and only appear annular because we are looking through
a greater thickness of gas at the edge of the shell. Shapley 1, however,
seems to be a true torus (doughnut-shape) seen face-on. Close inspection
reveals a faint outer halo.